Blowout preventer (BOP) test tool and methods

ABSTRACT

A test tool and related method for testing a blowout preventer (BOP). The test tool includes a first sub, a first pipe adapted to be connected to, and disconnected from, the first sub, the first pipe including an external spline, a second sub adapted to be connected to, and disconnected from, the first sub, the second sub including an internal spline adapted to engage the external spline of the first pipe, and a second pipe adapted to be connected to the second sub. The test tool includes an operational configuration in which the internal spline of the second sub engages the external spline of the first pipe so that a torque is transferable from the second sub to the first pipe via at least the engagement between the internal spline and the external spline. One or more high pressure low torque (HPLT) connections are incorporated into the test tool.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims the benefit of the filing date of, and priorityto, U.S. Application No. 62/338,207, filed May 18, 2016, the entiredisclosure of which is hereby incorporated herein by reference.

BACKGROUND

This disclosure relates in general to blowout preventers (BOPs) used inoil and gas exploration and production operations and, in particular, toa BOP test tool for testing BOPs, as well as to one or more highpressure low torque (HPLT) connections that are incorporated into thetest tool.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of a test tool for a blowout preventer, thetest tool including a bottom sub, a small pipe, a lower pin sub, and alarge pipe, according to an exemplary embodiment.

FIG. 2 is a sectional view of the bottom sub of FIG. 1, according to anexemplary embodiment.

FIG. 3 is a sectional view of the small pipe of FIG. 1, according to anexemplary embodiment.

FIG. 4 is an enlarged view of a portion of FIG. 3, according to anexemplary embodiment.

FIG. 5 is a sectional view of the lower pin sub of FIG. 1, according toan exemplary embodiment.

FIG. 6 is an enlarged view of a portion of FIG. 5, according to anexemplary embodiment.

FIG. 7 is a sectional view of the large pipe of FIG. 1, according to anexemplary embodiment.

FIG. 8 is a sectional view of the test tool of FIGS. 1-7 in a firstoperational configuration, according to an exemplary embodiment.

FIG. 9 is an enlarged view of a portion of FIG. 8, according to anexemplary embodiment.

FIG. 10 is an enlarged view of another portion of FIG. 8, according toan exemplary embodiment.

FIG. 11 is a sectional view of the test tool of FIGS. 1-7 in a secondoperational configuration, according to an exemplary embodiment.

FIG. 12 is an enlarged sectional view taken along the line 12-12 of FIG.11, according to an exemplary embodiment.

FIG. 13 is a sectional view of the test tool of FIGS. 1-7 in a thirdoperational configuration, according to an exemplary embodiment.

FIG. 14 is an elevational view of a system including a wellhead having ablowout preventer operably coupled thereto, the wellhead being sealinglyengaged by a plug to which the test tool of FIGS. 1-13 is operablycoupled in the first operational configuration, according to anexemplary embodiment.

FIG. 15 is an elevational view of the system of FIG. 14, the wellheadbeing sealingly engaged by a plug to which the test tool of FIGS. 1-13is operably coupled in the second operational configuration, accordingto an exemplary embodiment.

FIG. 16 is an elevational view of the system of FIGS. 14 and 15, thewellhead being sealingly engaged by a plug to which the test tool ofFIGS. 1-13 is operably coupled in the third operational configuration,according to an exemplary embodiment.

FIG. 17 is a flowchart illustration of a method for testing the BOP ofFIGS. 14-16 with the test tool of FIG. 1, according to an exemplaryembodiment.

DETAILED DESCRIPTION

In an exemplary embodiment, as illustrated in FIG. 1, a blowoutpreventer (BOP) test tool is generally referred to by the referencenumeral 10, and includes a bottom sub 12, a small pipe 14, a lower pinsub 16, and a large pipe 18. In one operational configuration, the smallpipe 14 and the lower pin sub 16 are each connected to the bottom sub12, the large pipe 18 is connected to the lower pin sub 16, and thesmall pipe 14 extends within the bottom sub 12, the lower pin sub 16,and the large pipe 18. In another operational configuration (shown inFIG. 1), the lower pin sub 16 is disconnected from the bottom sub 12 andthe small pipe 14 extends within the bottom sub 12 and the lower pin sub16. In yet another operational configuration, the small pipe 14 isdisconnected from the bottom sub 12. In operation, the test tool 10 isactuable between the above-described operational configurations to testa blowout preventer, as will be discussed in further detail below.

In an exemplary embodiment, as illustrated in FIG. 2 with continuingreference to FIG. 1, the bottom sub 12 is a generally tubular memberdefining upper and lower end portions 20 a and 20 b, and a longitudinalaxis 20 c. The bottom sub 12 includes a lower pin connection 22 at thelower end portion 20 b thereof. In an exemplary embodiment the lower pinconnection 22 is a 4½″ IF external threaded connection. In severalexemplary embodiments, instead of a 4½″ IF external threaded connection,the lower pin connection 22 is one of a wide variety of other typesand/or sizes of threaded connections. A pair of internal threadedconnections 24 and 26 are formed in the interior of the bottom sub 12.The internal threaded connection 26 is relatively larger than theinternal threaded connection 24, and is located proximate the upper endportion 20 a of the bottom sub 12. The internal threaded connection 24is located axially between the lower pin connection 22 and the internalthreaded connection 26.

Generally frusto-conical surfaces 28, 30, 32, and 34 are also formed inthe interior of the bottom sub 12. The surfaces 30 and 32 are locatedaxially between the internal threaded connections 24 and 26. The surface28 is located on a side of the internal threaded connection 24 oppositethe surface 30, at or near the lower end portion 20 b of the bottom sub12. The surface 34 is located on a side of the internal threadedconnection 26 opposite the surface 32, at or near the upper end portion20 a of the bottom sub 12.

In an exemplary embodiment, the surface 30 adjoins the internal threadedconnection 24 and extends upwardly and radially outwardly therefrom (asviewed in FIG. 2). The surface 30 defines an angle α1 with respect tothe longitudinal axis 20 c of the bottom sub 12. In several exemplaryembodiments, the angle α1 is about 50 degrees. In several exemplaryembodiments, the angle α1 is about 45 degrees. In several exemplaryembodiments, the angle α1 is between 45 and 50 degrees. In severalexemplary embodiments, the angle α1 is between 40 and 55 degrees.

In an exemplary embodiment, the surface 28 adjoins the internal threadedconnection 24 and extends downwardly and radially inwardly therefrom (asviewed in FIG. 2). However, the surfaces 28 and 30 need not adjoin theinternal threaded connection 24. The surface 28 defines an angle α2 withrespect to the longitudinal axis 20 c of the bottom sub 12. In severalexemplary embodiments, the angle α2 is about 50 degrees. In severalexemplary embodiments, the angle α2 is about 45 degrees. In severalexemplary embodiments, the angle α2 is between 45 and 50 degrees. Inseveral exemplary embodiments, the angle α2 is between 40 and 55degrees.

In an exemplary embodiment, the surface 32 adjoins the internal threadedconnection 26 and extends downwardly and radially inwardly therefrom (asviewed in FIG. 2). The surface 32 defines an angle α3 with respect tothe longitudinal axis 20 c of the bottom sub 12. In several exemplaryembodiments, the angle α3 is about 50 degrees. In several exemplaryembodiments, the angle α3 is about 45 degrees. In several exemplaryembodiments, the angle α3 is between 45 and 50 degrees. In severalexemplary embodiments, the angle α3 is between 40 and 55 degrees.

In an exemplary embodiment, the surface 34 adjoins the internal threadedconnection 26 and extends upwardly and radially outwardly therefrom (asviewed in FIG. 2). However, the surfaces 32 and 34 need not adjoin theinternal threaded connection 26. The surface 34 defines an angle α4 withrespect to the longitudinal axis 20 c of the bottom sub 12. In severalexemplary embodiments, the angle α4 is about 50 degrees. In severalexemplary embodiments, the angle α4 is about 45 degrees. In severalexemplary embodiments, the angle α4 is between 45 and 50 degrees. Inseveral exemplary embodiments, the angle α4 is between 40 and 55degrees.

In an exemplary embodiment, as illustrated in FIGS. 3 and 4 withcontinuing reference to FIG. 1, the small pipe 14 is a generally tubularmember defining upper and lower end portions 36 a and 36 b, and alongitudinal axis 36 c. An external threaded connection 38 is formed inthe exterior of the small pipe 14 at the lower end portion 36 b thereof,and is adapted to engage the internal threaded connection 24 of thebottom sub 12. In an exemplary embodiment, the external threadedconnection 38 is 4″ stub acme LH thread; in several exemplaryembodiments, other thread types and/or sizes may be used. Generallyfrusto-conical surfaces 40 and 42 (most clearly shown in FIG. 4) arealso formed in the exterior of the small pipe 14 at the lower endportion 36 b thereof.

In an exemplary embodiment, the surface 40 adjoins the external threadedconnection 38 and extends downwardly and radially inwardly therefrom (asviewed in FIG. 4). The surface 40 defines an angle β1 with respect tothe longitudinal axis 36 c of the small pipe 14. In several exemplaryembodiments, the angle β1 is about 50 degrees. In several exemplaryembodiments, the angle β1 is about 45 degrees. In several exemplaryembodiments, the angle β1 is between 45 and 50 degrees. In severalexemplary embodiments, the angle β1 is between 40 and 55 degrees. A pairof annular grooves 44 and 46 are formed in the surface 40 and adapted toaccommodate sealing elements 45 and 47 (shown in FIG. 9), respectively,for sealing engagement with the surface 28 of the bottom sub 12.

The surface 42 is located on a side of the external threaded connection38 opposite the surface 40, and is adapted to engage (or nearly engage)the surface 30 of the bottom sub 12. In an exemplary embodiment, thesurface 42 adjoins the external threaded connection 38 and extendsupwardly and radially outwardly therefrom (as viewed in FIG. 4).However, the surfaces 40 and 42 need not adjoin the external threadedconnection 38. The surface 42 defines an angle β2 with respect to thelongitudinal axis 36 c of the small pipe 14. In several exemplaryembodiments, the angle β2 is about 50 degrees. In several exemplaryembodiments, the angle β2 is about 45 degrees. In several exemplaryembodiments, the angle β2 is between 45 and 50 degrees. In severalexemplary embodiments, the angle β2 is between 40 and 55 degrees.

The small pipe 14 further includes a stop collar 48 at the upper endportion 36 a thereof, the stop collar 48 including an external spline 50(most clearly shown in FIG. 12). The stop collar 48 further defines oneor more axially-facing external surfaces adapted to engage the lower pinsub 16. The small pipe 14 also includes an upper box connection 52 atthe upper end portion 36 a thereof. In an exemplary embodiment the upperbox connection 52 is a 2⅞″ IF internal threaded connection. In severalexemplary embodiments, instead of a 2⅞″ IF internal threaded connection,the upper box connection 52 is one of a wide variety of other typesand/or sizes of threaded connections. In an exemplary embodiment, thesmall pipe 14 is 4½″ pipe. In several exemplary embodiments, the smallpipe 14 may be wide variety of sizes, greater in size than 4½″ pipe orless in size than 4½″ pipe.

In an exemplary embodiment, as illustrated in FIGS. 5 and 6 withcontinuing reference to FIG. 1, the lower pin sub 16 is a generallytubular member defining upper and lower end portions 54 a and 54 b, anda longitudinal axis 54 c. An external threaded connection 56 is formedin the exterior of the lower pin sub 16 at the lower end portion 54 bthereof, and is adapted to engage the internal threaded connection 26 ofthe bottom sub 12. In an exemplary embodiment, the external threadedconnection 56 is 7⅞″ stub acme LH thread; in several exemplaryembodiments, other thread types and/or sizes may be used. Generallyfrusto-conical surfaces 58 and 60 (most clearly shown in FIG. 6) arealso formed in the exterior of the lower pin sub 16 at the lower endportion 54 b thereof.

In an exemplary embodiment, the surface 58 adjoins the external threadedconnection 56 and extends downwardly and radially inwardly therefrom (asviewed in FIG. 6). The surface 58 defines an angle γ1 with respect tothe longitudinal axis 54 c of the lower pin sub 16. In several exemplaryembodiments, the angle γ1 is about 50 degrees. In several exemplaryembodiments, the angle γ1 is about 45 degrees. In several exemplaryembodiments, the angle γ1 is between 45 and 50 degrees. In severalexemplary embodiments, the angle γ1 is between 40 and 55 degrees. A pairof annular grooves 62 and 64 are formed in the surface 58 and adapted toaccommodate sealing elements 63 and 65 (shown in FIG. 9), respectively,for sealing engagement with the surface 32 of the bottom sub 12.

The surface 60 is located on a side of the external threaded connection56 opposite the surface 58. In an exemplary embodiment, the surface 60adjoins the external threaded connection 56 and extends upwardly andradially outwardly therefrom (as viewed in FIG. 6). However, thesurfaces 58 and 60 need not adjoin the external threaded connection 56.In several exemplary embodiments, the surface 60 defines an angle γ2with respect to the longitudinal axis 54 c of the lower pin sub 16. Inseveral exemplary embodiments, the angle γ2 is about 50 degrees. Inseveral exemplary embodiments, the angle γ2 is about 45 degrees. Inseveral exemplary embodiments, the angle γ2 is between 45 and 50degrees. In several exemplary embodiments, the angle γ2 is between 40and 55 degrees. An annular groove 66 is formed in the surface 60, and isadapted to accommodate a sealing element 67 (shown in FIG. 9) forsealing engagement with the surface 34 of the bottom sub 12.

The lower pin sub 16 further includes an internal threaded connection 68at the upper end portion 54 a thereof, and an internal shoulder 70adjacent the internal threaded connection 68. An internal spline 72 isformed in the interior of the lower pin sub 16 on a side of the internalshoulder 70 opposite the internal threaded connection 68. The internalspline 72 is adapted to be engaged by the external spline 50 of thesmall pipe 14. In several exemplary embodiments, a plurality ofcircumferentially-spaced threaded holes 74 are formed radially throughthe lower pin sub 16 adjacent the internal threaded connection 68. Inseveral exemplary embodiments, the lower pin sub 16 further includes acentralizer 76 having a plurality of centralizer blades (most clearlyshown in FIG. 1).

In an exemplary embodiment, as illustrated in FIG. 7 with continuingreference to FIG. 1, the large pipe 18 is a generally tubular memberdefining upper and lower end portions 78 a and 78 b. An externalthreaded connection 80 is formed in the exterior of the large pipe 18 atthe lower end portion 78 b thereof, and is adapted to engage theinternal threaded connection 68 of the lower pin sub 16. In an exemplaryembodiment, the external threaded connection 80 is 8¼″ stub acme LHthread; in several exemplary embodiments, other thread types and/orsizes may be used. An end face 82 and an annular notch 84 are alsoformed in the exterior of the large pipe 18 at the lower end portion 78b thereof. In an exemplary embodiment, the end face 82 adjoins theexternal threaded connection 80. A pair of annular grooves 86 and 88 areformed in the end face 82 and are adapted to accommodate sealingelements 87 and 89 (shown in FIG. 10), respectively, for sealingengagement with the internal shoulder 70 of the lower pin sub 16. Theannular notch 84 is located on a side of the external threadedconnection 80 opposite the end face 82, as is adapted to align with thethreaded holes 74 in the lower pin sub 16. In an exemplary embodiment,the annular notch 84 adjoins the external threaded connection 80.However, the end face 82 and the annular notch 84 need not adjoin theexternal threaded connection 80.

The large pipe 18 further includes an upper box connection 90 at theupper end portion 78 a thereof. In an exemplary embodiment the upper boxconnection 90 is a 4½″ IF internal threaded connection. In severalexemplary embodiments, instead of a 4½″ IF internal threaded connection,the upper box connection 90 is one of a wide variety of other typesand/or sizes of threaded connections. In an exemplary embodiment, thelarge pipe 18 is 6⅝″ pipe. In several exemplary embodiments, the largepipe 18 may be a wide variety of sizes, greater in size than 6⅝″ pipe orless in size than 6⅝″ pipe.

Turning to FIGS. 8-10, with continuing reference to FIGS. 1-7, the testtool 10 is illustrated in a first operational (or “run-in”)configuration, in which the small pipe 14 is connected to the bottom sub12 and positioned in a first axial position relative to the bottom sub12, and the lower pin sub 16 is connected to the bottom sub 12 andpositioned in a first axial position relative to the small pipe 14. Inseveral exemplary embodiments, the first operational configuration ofthe test tool 10 is characterized by the small pipe 14 being connectedto the bottom sub 12, the lower pin sub 16 being connected to the bottomsub 12, the large pipe 18 being connected to the lower pin sub 16, andthe small pipe 14 extending within the bottom sub 12, the lower pin sub16, and the large pipe 18. More particularly, the external threadedconnection 38 of the small pipe 14 threadably engages the internalthreaded connection 24 of the bottom sub 12 so that the sealing elements45 and 47 in the annular grooves 44 and 46, respectively, of the smallpipe 14 sealingly engage the surface 28 of the bottom sub 12, and thesurface 42 of the small pipe 14 engages (or nearly engages) the surface30 of the bottom sub 12 (most clearly shown in FIG. 9). In severalexemplary embodiments, one or both of the sealing elements 45 and 47 inthe annular grooves 44 and 46 form a metal-to-metal seal with thesurface 28 of the bottom sub 12. However, the sealing element 47 in theannular groove 46 may be an elastomeric back-up seal. As a result, thesmall pipe 14 sealingly engages the bottom sub 12.

In several exemplary embodiments, the strength of the sealing engagementbetween the surface 28 of the bottom sub 12 and the sealing elements 45and 47 in the annular grooves 44 and 46 is improved by the angle α2 ofthe surface 28 with respect to the longitudinal axis 20 c, the angle β1of the surface 40 with respect to the longitudinal axis 36 c, theconfiguration of the sealing elements 45 and 47 in the annular grooves44 and 46, or any combination thereof. This improved sealing arrangementis not limited to the test tool 10, and may be incorporated into otheroil and gas equipment and/or downhole tools.

In several exemplary embodiments, a high pressure low torque (HPLT)connection of the test tool 10 is facilitated by the combination of: thethreaded engagement between the external threaded connection 38 of thesmall pipe 14 and the internal threaded connection 24 of the bottom sub12; and the sealing engagement between the surface 28 of the bottom sub12 and the sealing elements 45 and 47 in the annular grooves 44 and 46.This HPLT connection is made possible, at least in part, by the angle α2of the surface 28 with respect to the longitudinal axis 20 c, the angleβ1 of the surface 40 with respect to the longitudinal axis 36 c, theconfiguration of the sealing elements 45 and 47 in the annular grooves44 and 46, or any combination thereof. In operation, the application ofa torque not exceeding 3,000 ft-lbs to connect the small pipe 14 to thebottom sub 12 enables the HPLT connection therebetween to withstand insitu pressures of up to 25,000 psi. The use of this HPLT connection isnot limited to the test tool 10, and may be incorporated into other oiland gas equipment and tools, including downhole tools.

Additionally, the external threaded connection 56 of the lower pin sub16 threadably engages the internal threaded connection 26 of the bottomsub 12 so that the sealing elements 63 and 65 in the annular grooves 62and 64, respectively, of the lower pin sub 16 sealingly engage thesurface 32 of the bottom sub 12 and the sealing element 67 in theannular groove 66 of the lower pin sub 16 sealingly engages the surface34 of the bottom sub 12 (most clearly shown in FIG. 9). In severalexemplary embodiments, one or both of the sealing elements 63 and 65 inthe annular grooves 62 and 64 form a metal-to-metal seal with thesurface 32 of the bottom sub 12. Moreover, in several exemplaryembodiments, the sealing element 67 in the annular groove 66 forms ametal-to-metal seal with the surface 34 of the bottom sub 12. However,the sealing elements 65 and 67 in the annular grooves 64 and 66,respectively, may be elastomeric back-up seals. As a result, the lowerpin sub 16 extends about the small pipe 14 and sealingly engages thebottom sub 12.

In several exemplary embodiments, the strength of the sealing engagementbetween the surface 32 of the bottom sub 12 and the sealing elements 63and 65 in the annular grooves 62 and 64 is improved by the angle α3 ofthe surface 32 with respect to the longitudinal axis 20 c, the angle γ1of the surface 58 with respect to the longitudinal axis 54 c, theconfiguration of the sealing elements 63 and 65 in the annular grooves62 and 64, or any combination thereof. In several exemplary embodiments,the strength of the sealing engagement between the surface 34 of thebottom sub 12 and the sealing element 67 in the annular groove 66 isimproved by the angle α4 of the surface 34 with respect to thelongitudinal axis 20 c, the angle γ2 of the surface 60 with respect tothe longitudinal axis 54 c, the configuration of the sealing element 67in the annular groove 66, or any combination thereof. These improvedsealing arrangements are not limited to the test tool 10, and may beincorporated into other oil and gas equipment and tools, includingdownhole tools.

In several exemplary embodiments, another HPLT connection of the testtool 10 is facilitated by the combination of: the threaded engagementbetween the external threaded connection 56 of the lower pin sub 16 andthe internal threaded connection 26 of the bottom sub 12; and thesealing engagement between the surface 32 of the bottom sub 12 and oneor both of the sealing elements 63 and 65 in the annular grooves 62 and64. This HPLT connection is made possible, at least in part, by theangle α3 of the surface 32 with respect to the longitudinal axis 20 c,the angle γ1 of the surface 58 with respect to the longitudinal axis 54c, the configuration of one or both of the sealing elements 63 and 65 inthe annular grooves 62 and 64, or any combination thereof. In severalexemplary embodiments, the another HPLT connection of the test tool 10is also facilitated by the sealing engagement between the surface 34 ofthe bottom sub 12 and the sealing element 67 in the annular groove 66.In such embodiments, the another HPLT connection is made possible, atleast in part, by the angle α4 of the surface 34 with respect to thelongitudinal axis 20 c, the angle γ2 of the surface 60 with respect tothe longitudinal axis 54 c, the configuration of the sealing element 67in the annular groove 66, or any combination thereof. In operation, theapplication of a torque not exceeding 3,000 ft-lbs to connect the lowerpin sub 16 to the bottom sub 12 enables the HPLT connection therebetweento withstand in situ pressures of up to 25,000 psi. The use of this HPLTconnection is not limited to the test tool 10, and may be incorporatedinto other oil and gas equipment and/or downhole tools.

Finally, the external threaded connection 80 of the large pipe 18threadably engages the internal threaded connection 68 of the lower pinsub 16 so that the sealing elements 87 and 89 in the annular grooves 86and 88, respectively, of the large pipe 18 sealingly engage the internalshoulder 70 of the lower pin sub 16 and the annular notch 84 in thelarge pipe 18 aligns with the threaded holes 74 in the lower pin sub 16(most clearly shown in FIG. 10). A plurality of set screws 92 arethreadably engaged with the threaded holes 74 and extend within theannular notch 84 to maintain the threaded engagement between theexternal threaded connection 80 and the internal threaded connection 68.As a result, the large pipe 18 extends about the small pipe 14 andsealingly engages the lower pin sub 16.

Turning to FIGS. 11 and 12, the test tool 10 is illustrated in a secondoperational configuration, in which the small pipe 14 is connected tothe bottom sub 12 and positioned in the first axial position relative tothe bottom sub 12, and the lower pin sub 16 is disconnected from thebottom sub 12 and positioned in a second axial position relative to thesmall pipe 14. The internal spline 72 of the lower pin sub 16 engagesthe external spline 50 of the small pipe 14 when the lower pin sub 16 isin the second axial position relative to the small pipe 14. As a result,torque is transferable from the lower pin sub 16 to the small pipe 14via at least the engagement between the internal spline 72 and theexternal spline 50. In several exemplary embodiments, the secondoperational configuration of the test tool 10 is characterized by thesmall pipe 14 being connected to the bottom sub 12, the lower pin sub 16being disconnected from the bottom sub 12, the large pipe 18 beingconnected to the lower pin sub 16, and the small pipe 14 extendingwithin the bottom sub 12 and the lower pin sub 16.

More particularly, the external threaded connection 56 of the lower pinsub 16 is disengaged from the internal threaded connection 26 of thebottom sub 12, and the lower pin sub 16 and the large pipe 18 arerepositioned relative to the bottom sub 12 and the small pipe 14. As aresult, the external spline 50 of the small pipe 14 engages the internalspline 72 of the lower pin sub 16 (shown most clearly in FIG. 12).Additionally, the external threaded connection 38 of the small pipe 14remains threadably engaged with the internal threaded connection 24 ofthe bottom sub 12. As a result, the small pipe 14 remains sealinglyengaged with the bottom sub 12. Finally, the external threadedconnection 80 of the large pipe 18 remains threadably engaged with theinternal threaded connection 68 of the lower pin sub 16, and theplurality of set screws 92 remain engaged with the threaded holes 74 andthe annular notch 84 to maintain the threaded engagement between theexternal threaded connection 80 and the internal threaded connection 68.As a result, the large pipe 18 remains sealingly engaged with the lowerpin sub 16.

Turning to FIG. 13, the test tool 10 is illustrated in a thirdoperational configuration, in which the small pipe 14 is disconnectedfrom the bottom sub 12 and positioned in a second axial positionrelative to the bottom sub 12, and the lower pin sub 16 is disconnectedfrom the bottom sub 12 and positioned in the second axial positionrelative to the small pipe 14. In several exemplary embodiments, thethird operational configuration of the test tool 10 is characterized bythe small pipe 14 being disconnected from the bottom sub 12, the lowerpin sub 16 being disconnected from the bottom sub 12, the large pipe 18being connected to the lower pin sub 16, and the small pipe 14 extendingwithin the lower pin sub 16. More particularly, the external threadedconnection 38 of the small pipe 14 is disengaged from the internalthreaded connection 24 of the bottom sub 12, and the small pipe 14, thelower pin sub 16, and the large pipe 18 are repositioned relative to thebottom sub 12. As a result, an empty space is defined between the bottomsub 12 and the small pipe 14. Additionally, the external spline 50 ofthe small pipe 14 remains engaged with the internal spline 72 of thelower pin sub 16. Indeed, this engagement between the external spline 50and the internal spline 72 facilitates the actuation of the test tool 10from the second configuration to the third configuration, as will bediscussed in further detail below. Finally, the external threadedconnection 80 of the large pipe 18 remains threadably engaged with theinternal threaded connection 68 of the lower pin sub 16, and theplurality of set screws 92 remain engaged with the threaded holes 74 andthe annular notch 84 to maintain the threaded engagement between theexternal threaded connection 80 and the internal threaded connection 68.As a result, the large pipe 18 remains sealingly engaged with the lowerpin sub 16.

In an exemplary embodiment, as illustrated in FIGS. 14-16, a system isgenerally referred to by the reference numeral 94 and includes awellhead 96 and a blowout preventer (BOP) 98 operably coupled thereto.The wellhead 96 is located at the top or head of an oil and gaswellbore, which penetrates one or more subterranean formations. Thewellhead 96 is used in oil and gas exploration and productionoperations. The wellhead 96 may be a subsea wellhead or a surfacewellhead. The wellhead 96 may be located offshore or onshore. The BOP 98is configured to seal off the wellbore at the top of which the wellhead96 is disposed in order to, for example, prevent uncontrolled releasesof oil and gas from the wellbore (i.e., wellbore blowouts). The BOP 98may include one or more annular preventers 100, and/or may include oneor more rams such as, for example, one or more variable bore rams (VBR)102, one or more shear rams 104 (including, for example, one or moreblind shear rams (BSR) and one or more casing shear rams (CSR)), one ormore other types of rams, or any combination thereof. The BOP 98 may be,or include, an annular BOP, a ram BOP, or a combination thereof. The BOP98 may include any type of BOP stack. In several exemplary embodiments,the system of FIGS. 14-16 includes other components or systems such as,for example, one or more drilling risers.

The wellhead 96 is sealed off, or at least sealingly engaged, by a plug106 to which the test tool 10 is operably coupled. In several exemplaryembodiments, the plug 106 includes one or more sealing elements. Inseveral exemplary embodiments, the lower pin connection 22 of the bottomsub 12 of the test tool 10 is connected to the plug 106. Alternatively,a spacer 108 and/or a crossover 110 may be connected between the testtool 10 and the plug 106. In operation, the test tool 10 is used to testthe different rams of the BOP 98 to ensure that the BOP 98 is insufficient working order, as will be discussed in further detail below.The test tool 10 may be used to test a wide variety of rams of the BOP98 including, but not limited to, the VBR rams 102, the shear rams 104(including the BSR rams and the CSR rams), other types of rams, or anycombination thereof. During testing, at least a portion of the test tool10 extends within an internal passage defined by the BOP 98. In severalexemplary embodiments, the test tool 10 is, or is part of, a tubularstring that extends through the BOP 98; in several exemplaryembodiments, the tubular string may extend upwards, or in anotherdirection from the BOP 98.

In an exemplary embodiment, as illustrated in FIG. 17 with continuingreference to FIGS. 14-16, a method of testing the BOP 98 is generallyreferred to by the reference numeral 112 and includes operably couplingthe plug 106 to the bottom sub 12 of the test tool 10 at step 114;running the test tool 10 into the BOP 98 in the first operationalconfiguration at step 116; sealingly engaging the plug 106 with thewellhead 96 at step 118; testing the BOP 98 on the large pipe 18 at step120; actuating the test tool 10 from the first operational configurationto the second operational configuration at step 122; testing the BOP 98on the small pipe 14 at step 124; actuating the test tool 10 from thesecond operational configuration to the third operational configurationat step 126; and testing the BOP on the empty space between the bottomsub 12 and the small pipe 14 at step 128.

In an exemplary embodiment of the step 114, the plug 106 is operablycoupled to the bottom sub 12 of the test tool 10. More particularly, thetest tool 10 is connected to the plug 106 using the lower pin connection22 at the lower end portion 20 b of the bottom sub 12.

In an exemplary embodiment of the step 116, the test tool 10 is run intothe BOP 98 in the first operational configuration (shown in FIGS. 8-10).More particularly, in the first operational configuration, the smallpipe 14 is connected to the bottom sub 12 and positioned in the firstaxial position relative to the bottom sub 12, the large pipe 18 isconnected to the lower pin sub 16, and the lower pin sub 16 is connectedto the bottom sub 12 and positioned in the first axial position relativeto the small pipe 14 so that the small pipe 14 extends within the bottomsub 12, the lower pin sub 16, and the large pipe 18. As a result, thetest tool 10 extends within the BOP 98 and is connected to the plug 106.

In an exemplary embodiment of the step 118, the plug 106 is sealinglyengaged with the wellhead 96. In several exemplary embodiments,sealingly engaging the plug 106 with the wellhead 96 seals off thewellhead 96.

In an exemplary embodiment of the step 120, the BOP 98 is tested on thelarge pipe 18, as shown in FIG. 14. More particularly, when the testtool 10 is in the first operational configuration (shown in FIGS. 8-10),the one or more annular preventers 100 and/or the one or more rams 102and 104 of the BOP 98 may be tested using the large pipe 18. In severalexemplary embodiments, the one or more annular preventers 100 and/or theone or more rams 102 and 104 many engage the outside surface of thelarge pipe 18. In several exemplary embodiments, the one or more rams102 and 104 may be or include the VBR pipe rams. In several exemplaryembodiments, the large pipe 18 may be filled with fluid during thistesting. In several exemplary embodiments, the small pipe 14 may befilled with fluid during this testing. In several exemplary embodiments,the large pipe 18 and the small pipe 14 may be filled with fluid duringthis testing.

In an exemplary embodiment of the step 122, the test tool 10 is actuatedfrom the first operational configuration (shown in FIGS. 8-10) to thesecond operational configuration (shown in FIGS. 11 and 12). Moreparticularly, after the completion of any desired testing of the one ormore annular preventers 100 and/or the one or more rams 102 and 104 ofthe BOP 98 using the large pipe 18, the lower pin sub 16 is disengagedfrom the bottom sub 12 by turning or rotating the large pipe 18 (or thestring or another tool or device connected to the large pipe 18), andthus the lower pin sub 16 connected thereto, in a first rotationaldirection. In an exemplary embodiment, the external threaded connection56 at the lower end portion 54 b of the lower pin sub 12 is left-hand(LH) Stub Acme thread, and the lower pin sub 16 is rotated or turnedclockwise to effect the disengagement from the bottom sub 12.

Subsequently, the large pipe 18, and thus the lower pin sub 16 connectedthereto, are lifted or pulled upwards (moving bottom to top as viewed inFIG. 15), increasing the separation distance between the lower pin sub16 and the bottom sub 12. As a result, the internal spline 72 of thelower pin sub 16 approaches the external spline 50 of the stop collar 48at the upper end portion 36 a of the small pipe 14, and the internalspline 72 engages the external spline 50. The large pipe 18, and thusthe lower pin sub 16 connected thereto, continues to be lifted (movingbottom to top as viewed in FIG. 15) until: the internal spline 72 of thelower pin sub 16 is engaged with the external spline 50 of the stopcollar 48 at the upper end portion 36 a of the small pipe 14, and adownward axially-facing external surface of the stop collar 48 engagesan upward axially-facing internal surface of the lower pin sub 16, whichinternal surface is at the lower end portion 54 b of the lower pin sub16, proximate the external threaded connection 56 thereof (shown inFIGS. 11 and 12).

As a result, in the second operational configuration, the small pipe 14is connected to the bottom sub 12 and positioned in the first axialposition relative to the bottom sub 12, the large pipe 18 is connectedto the lower pin sub 16, and the lower pin sub 16 is disconnected fromthe bottom sub 12 and positioned in the second axial position relativeto the small pipe 14 so that the small pipe 14 extends within the bottomsub 12 and the lower pin sub 16. When the lower pin sub 16 is positionedin the second axial position relative to the small pipe 14, a torque istransferable from the lower pin sub 16 to the small pipe 14. This torqueis transferable from the lower pin sub 16 to the small pipe 14 via theengagement between the internal spline 72 of the lower pin sub 16 andthe external spline 50 of the small pipe 14 when the lower pin sub 16 ispositioned in the second axial position relative to the small pipe 14.

In an exemplary embodiment of the step 124, the BOP 98 is tested on thesmall pipe 14, as shown in FIG. 15. More particularly, when the testtool 10 is in the second operational configuration (shown in FIGS. 11and 12), the one or more annular preventers 100 and/or the one or morerams 102 and 104 of the BOP 98 may be tested using the small pipe 14. Inseveral exemplary embodiments, the one or more annular preventers 100and/or the one or more rams 102 and 104 may engage the outside surfaceof the small pipe 14. In several exemplary embodiments, the one or morerams 102 and 104 may be the VBR pipe rams. In several exemplaryembodiments, the small pipe 14 may be filled with fluid during thistesting. In several exemplary embodiments, the large pipe 18 may befilled with fluid during this testing. In several exemplary embodiments,the small pipe 14 and the large pipe 18 may be filled with fluid duringthis testing.

In an exemplary embodiment of the step 126, the test tool 10 is actuatedfrom the second operational configuration (shown in FIGS. 11 and 12) tothe third operational configuration (shown in FIG. 13). Moreparticularly, after the completion of any desired testing of the one ormore annular preventers 100 and/or the one or more rams 102 and 104 ofthe BOP 98 using the small pipe 14, the small pipe 14 is disengaged fromthe bottom sub 12. The small pipe 14 is rotated or turned in the firstrotational direction so that the external threaded connection 38 at thelower end portion 36 b of the small pipe 14 is disengaged from theinternal threaded connection 24 of the bottom sub 12. In an exemplaryembodiment, the first rotational direction in which the small pipe 14 isrotated is a clockwise direction; that is, the small pipe 14 is rotatedclockwise so that the small pipe 14 disengages from the bottom sub 12.In an exemplary embodiment, to rotate the small pipe 14, the large pipe18 (or the string or another tool or device connected to the large pipe18) is rotated. Since the lower pin sub 16 is connected to the largepipe 18, the lower pin sub 16 also rotates. Since torque is transferablefrom the lower pin sub 16 to the small pipe 14 via at least theengagement between the internal spline 72 of the lower pin sub 16 andthe external spline 50 of the small pipe 14, the small pipe 14 alsorotates, causing the small pipe 14 to disengage from the bottom sub 12(which is connected to the plug 106 that sealingly engages the wellhead96). In an exemplary embodiment, the external threaded connection 38 atthe lower end portion 36 b of the small pipe 14 is left-hand (LH) StubAcme thread, and the small pipe 14 is rotated or turned clockwise toeffect the disengagement from the bottom sub 12.

Subsequently, after the small pipe 14 is disengaged from the bottom sub12, the large pipe 18 is lifted upwards, causing the small pipe 14 to belifted upwards (bottom to top as viewed in FIG. 16) and away from thebottom sub 12. The connection between the lower pin sub 16 and the largepipe 18 causes the lower pin sub 16 to be lifted upwards in response tothe large pipe 18 being lifted upwards. The engagement between theinternal surface of the lower pin sub 16 and the external surface of thestop collar 48 of the small pipe 14 causes the small pipe 14 to belifted upwards in response to the lower pin sub 16 being lifted upwards.The engagement between the internal spline 72 and the external spline 50prevents appreciable relative rotation between the lower pin sub 16 andthe small pipe 14. As shown in FIG. 16, an axial spacing is definedbetween the lower end portion 36 b of the small pipe 14 and the bottomsub 12.

As a result, in the third operational configuration, the small pipe 14is disconnected from the bottom sub 12 and positioned in the secondaxial position relative to the bottom sub 12, the large pipe 18 isconnected to the lower pin sub 16, and the lower pin sub 16 isdisconnected from the bottom sub 12 and positioned in the second axialposition relative to the small pipe 14 so that the small pipe 14 extendswithin the lower pin sub 16. When the small pipe 14 is positioned in thesecond axial position relative to bottom sub 12, the small pipe 14 isspaced apart from the bottom sub 12.

In an exemplary embodiment of the step 128, the BOP 98 is tested on theempty space between the lower end portion 36 b of the small pipe 14 andthe bottom sub 12 (shown in FIG. 16). More particularly, when the testtool 10 is in the third operational configuration (shown in FIG. 13),the one or more shear rams 104 of the BOP 98 may be tested using theaxial spacing defined between the lower end portion 36 b of the smallpipe 14 and the bottom sub 12. In several exemplary embodiments, the oneor more shear rams 104 may be the blind shear rams (BSR), the casingshear rams (CSR), other types of shear rams, or any combination thereof.In several exemplary embodiments, during the testing of the one or moreshear rams 104 of the BOP 98, the one or more shear rams 104 move intothe axial spacing defined between the lower end portion 36 b of thesmall pipe 14 and the bottom sub 12. As a result, the test tool 10 isnot damaged due to the testing of the shear rams 104 of the BOP 98.

In several exemplary embodiments, after the completion of any desiredtesting of the one or more shear rams 104 of the BOP 98 using the axialspacing defined between the lower end portion 36 b of the small pipe 14and the bottom sub 12, the method 112 further includes lowering thesmall pipe 14 back into the bottom sub 12. However, no threadedengagement is made between the external threaded connection 38 of thesmall pipe 14 and the internal threaded connection 24 of the bottom sub12. The large pipe 18 is lowered, causing the lower pin sub 16 and thesmall pipe 14 to be lowered. The lowering is stopped when the small pipe14 contacts the bottom sub 12.

In several exemplary embodiments, after the small pipe 14 contacts thebottom sub 12, the method 112 further includes lowering the large pipe18 and the lower pin sub 16, thereby disengaging the internal spline 72of the lower pin sub 16 from the external spline 50 of the stop collar48 of the small pipe 14. After further lowering, the external threadedconnection 56 of the lower pin sub 16 is threadably engaged with theinternal threaded connection 26 of the bottom sub 12. In an exemplaryembodiment, the respective threaded connections 26 and 56 are left handthreads and the large pipe 18, and thus the lower pin sub 16, arerotated counterclockwise to effect the threaded engagement between theexternal threaded connection 56 and the internal threaded connection 26.Subsequently, the test tool 10 is pulled up and out of the BOP 98.

During the above-described operation of the test tool 10, thecentralizer 76 of the lower pin sub 16 centralizes the test tool 10within the internal passage defined by the BOP 98.

In several exemplary embodiments, the above-described operation of thetest tool 10 facilitates testing of the one or more annular preventer100 and/or the one or more rams 102 and 104 of BOP 98 in a single trip.

In several exemplary embodiments, the small pipe 14 and the large pipe18 are used to test the one or more rams 102 and 104 in the BOP 98,which rams 102 and 104 engage the exterior surface of the small pipe 14and/or the large pipe 18. In several exemplary embodiments, in additionto the small pipe 14 and the large pipe 18, additional pipes or tubesmay be added to the test tool 10 to be used to test the one or more rams102 and 104. In several exemplary embodiments, instead of, or inaddition to one or both of the small pipe 14 and the large pipe 18, oneor more other pipes or tubes of different sizes (less than 4½″, greaterthan 4½″, less than 6⅝″, greater than 6⅝″, etc.) may be included in thetest tool 10.

In several exemplary embodiments, each of thread types and/or threadedconnections described above and/or illustrated in the figures may be anytype of connection (Stub Acme, All Premium Thread, VAM, Hunting,Teneris, all standard threads and thread types, etc.).

In several exemplary embodiments, each of the components described aboveand/or illustrated in the figures may be fabricated from a wide varietyof materials including, but not limited to, one or more metallicmaterials, one or more plastic materials, one or more steel alloys, oneor more aluminum alloys, or any combination thereof.

In several exemplary embodiments, the test tool 10 is a universal BOPtest tool in that is capable of testing a wide variety of rams of a BOPusing either axial spacing and/or pipes having a wide range of sizes.

In an exemplary embodiment, a method includes testing one or more ramsof a BOP with the largest-sized pipe or tube of a test tool, thentesting one or more rams of the BOP using the second largest-sized pipeor tube of the test tool, then testing one or more rams of the BOP usingthe third largest-sized pipe or tube of the test tool, and so on untilthe smallest-sized pipe or tube has been used to test one or more ramsof the BOP, after which an axial spacing is defined between thesmallest-sized pipe or tube and the bottom sub, and one or more shearrams of the BOP are tested by moving the one or more shear rams into theaxial spacing. The above-described test tool 10 may be used to carry outthis method, and additional tubes and corresponding components may beadded to the test tool 10 (as necessary or required).

The present disclosure introduces a test tool for a blowout preventer,the test tool including a first sub; a first pipe adapted to beconnected to, and disconnected from, the first sub, the first pipeincluding an external spline; a second sub adapted to be connected to,and disconnected from, the first sub, the second sub including aninternal spline adapted to engage the external spline of the first pipeso that a torque is transferable from the second sub to the first pipe;and a second pipe adapted to be connected to the second sub. In anexemplary embodiment, when the first pipe is connected to the first sub,an external threaded connection of the first pipe is connected to afirst internal threaded connection of the first sub; and, when thesecond sub is connected to the first sub, an external threadedconnection of the second sub is connected to a second internal threadedconnection of the first sub. In an exemplary embodiment, when theexternal threaded connection of the first pipe is connected to the firstinternal threaded connection of the first sub: first and secondgenerally frusto-conical surfaces of the first sub are engaged, ornearly engaged, by first and second generally frusto-conical surfaces ofthe first pipe; and one or more sealing elements extending within one ormore annular grooves in the first surface of the first pipe sealinglyengage the first surface of the first sub. In an exemplary embodiment,when the external threaded connection of the second sub is connected tothe second internal threaded connection of the first sub: third andfourth generally frusto-conical surfaces of the first sub are engaged,or nearly engaged, by first and second generally frusto-conical surfacesof the second sub; and one or more sealing elements extending within oneor more annular grooves in the first and second surfaces of the secondsub sealingly engage the third and fourth surfaces of the first sub. Inan exemplary embodiment, the test tool further includes a firstoperational configuration in which: the first pipe is connected to thefirst sub and positioned in a first axial position relative to the firstsub; the second pipe is connected to the second sub; and the second subis connected to the first sub and positioned in a first axial positionrelative to the first pipe so that the first pipe extends within thefirst sub, the second sub, and the second pipe. In an exemplaryembodiment, the test tool further includes a second operationalconfiguration in which: the first pipe is connected to the first sub andpositioned in the first axial position relative to the first sub; thesecond pipe is connected to the second sub; and the second sub isdisconnected from the first sub and positioned in a second axialposition relative to the first pipe so that the first pipe extendswithin the first sub and the second sub. In an exemplary embodiment,when the second sub is positioned in the second axial position relativeto the first pipe, the internal spline of the second sub engages theexternal spline of the first pipe so that the torque is transferablefrom the second sub to the first pipe via at least the engagementbetween the internal spline and the external spline. In an exemplaryembodiment, the test tool further includes a third operationalconfiguration in which: the first pipe is disconnected from the firstsub and positioned in a second axial position relative to the first sub;the second pipe is connected to the second sub; and the second sub isdisconnected from the first sub and positioned in the second axialposition relative to the first pipe so that the first pipe extendswithin the second sub. In an exemplary embodiment, when the first pipeis positioned in the second axial position relative to first sub, thefirst pipe is spaced apart from the first sub.

The present disclosure also introduces a tool for testing a blowoutpreventer operably coupled to a wellhead, the tool including a first subadapted to be connected to a plug that sealingly engages the wellhead; afirst pipe adapted to be connected to, and disconnected from, the firstsub; a second sub adapted to be connected to, and disconnected from, thefirst sub; and a second pipe adapted to be connected to the second sub;a first operational configuration in which: the first pipe is connectedto the first sub and positioned in a first axial position relative tothe first sub; the second pipe is connected to the second sub; and thesecond sub is connected to the first sub and positioned in a first axialposition relative to the first pipe so that the first pipe extendswithin the first sub, the second sub, and the second pipe; and a secondoperational configuration in which: the first pipe is connected to thefirst sub and positioned in the first axial position relative to thefirst sub; the second pipe is connected to the second sub; and thesecond sub is disconnected from the first sub and positioned in a secondaxial position relative to the first pipe so that the first pipe extendswithin the first sub and the second sub, wherein, when the second sub ispositioned in the second axial position relative to the first pipe, atorque is transferable from the second sub to the first pipe. In anexemplary embodiment, the torque is transferable from the second sub tothe first pipe via an engagement between an internal spline of thesecond sub and an external spline of the first pipe when the second subis positioned in the second axial position relative to the first pipe.In an exemplary embodiment, the tool further includes a thirdoperational configuration in which: the first pipe is disconnected fromthe first sub and positioned in a second axial position relative to thefirst sub; the second pipe is connected to the second sub; and thesecond sub is disconnected from the first sub and positioned in thesecond axial position relative to the first pipe so that the first pipeextends within the second sub. In an exemplary embodiment, when thefirst pipe is positioned in the second axial position relative to firstsub, the first pipe is spaced apart from the first sub. In an exemplaryembodiment, when the first pipe is connected to the first sub, anexternal threaded connection of the first pipe is connected to a firstinternal threaded connection of the first sub; and, when the second subis connected to the first sub, an external threaded connection of thesecond sub is connected to a second internal threaded connection of thefirst sub. In an exemplary embodiment, when the external threadedconnection of the first pipe is connected to the first internal threadedconnection of the first sub: first and second generally frusto-conicalsurfaces of the first sub are engaged, or nearly engaged, by first andsecond generally frusto-conical surfaces of the first pipe; and one ormore sealing elements extending within one or more annular grooves inthe first surface of the first pipe sealingly engage the first surfaceof the first sub. In an exemplary embodiment, when the external threadedconnection of the second sub is connected to the second internalthreaded connection of the first sub: third and fourth generallyfrusto-conical surfaces of the first sub are engaged, or nearly engaged,by first and second generally frusto-conical surfaces of the second sub;and one or more sealing elements extending within one or more annulargrooves in the first and second surfaces of the second sub sealinglyengage the third and fourth surfaces of the first sub.

The present disclosure also introduces a method of testing a blowoutpreventer (BOP), the method including providing a test tool, the testtool including: a first sub; a first pipe adapted to be connected to,and disconnected from, the first sub; a second sub adapted to beconnected to, and disconnected from, the first sub; and a second pipeadapted to be connected to the second sub; running the test tool intothe BOP in a first operational configuration in which: the first pipe isconnected to the first sub and positioned in a first axial positionrelative to the first sub; the second pipe is connected to the secondsub; and the second sub is connected to the first sub and positioned ina first axial position relative to the first pipe so that the first pipeextends within the first sub, the second sub, and the second pipe; andactuating the test tool from the first operational configuration to asecond operational configuration in which: the first pipe is connectedto the first sub and positioned in the first axial position relative tothe first sub; the second pipe is connected to the second sub; and thesecond sub is disconnected from the first sub and positioned in a secondaxial position relative to the first pipe so that the first pipe extendswithin the first sub and the second sub, wherein, when the second sub ispositioned in the second axial position relative to the first pipe, atorque is transferable from the second sub to the first pipe. In anexemplary embodiment, the method further includes actuating the testtool from the second operational configuration to a third operationalconfiguration in which: the first pipe is disconnected from the firstsub and positioned in a second axial position relative to the first sub;the second pipe is connected to the second sub; and the second sub isdisconnected from the first sub and positioned in the second axialposition relative to the first pipe so that the first pipe extendswithin the second sub. In an exemplary embodiment, when the first pipeis positioned in the second axial position relative to first sub, thefirst pipe is spaced apart from the first sub. In an exemplaryembodiment, actuating the test tool from the first operationalconfiguration to the second operational configuration includes: rotatingthe second sub relative to the first sub to threadably disengage anexternal threaded connection of the second sub from a first internalthreaded connection of the first sub; and axially displacing the secondsub relative to the first pipe from the first axial position to thesecond axial position. In an exemplary embodiment, actuating the testtool from the second operational configuration to the third operationalconfiguration includes: rotating the first pipe relative to the firstsub to threadably disengage an external threaded connection of the firstpipe from a second internal threaded connection of the first sub; andaxially displacing the first pipe relative to the first sub from thefirst axial position to the second axial position. In an exemplaryembodiment, rotating the first pipe relative to the first sub includestransferring the torque from the second sub to the first pipe via anengagement between an internal spline of the second sub and an externalspline of the first pipe. In an exemplary embodiment, when the firstpipe is connected to the first sub: first and second generallyfrusto-conical surfaces of the first sub are engaged, or nearly engaged,by first and second generally frusto-conical surfaces of the first pipe;and one or more sealing elements extending within one or more annulargrooves in the first surface of the first pipe sealingly engage thefirst surface of the first sub. In an exemplary embodiment, when thesecond sub is connected to the first sub: third and fourth generallyfrusto-conical surfaces of the first sub are engaged, or nearly engaged,by first and second generally frusto-conical surfaces of the second sub;and one or more sealing elements extending within one or more annulargrooves in the first and second surfaces of the second sub sealinglyengage the third and fourth surfaces of the first sub.

The present disclosure also introduces a method of testing a blowoutpreventer (BOP) operably coupled to a wellhead, the method includingoperably coupling a test tool to a plug that is adapted to sealinglyengage the wellhead, the test tool including: a first sub; and a firstpipe adapted to be connected to, and disconnected from, the first sub; asecond sub adapted to be connected to, and disconnected from, the firstsub; and a second pipe adapted to be connected to the second sub;sealingly engaging the plug with the wellhead so that the test toolextends within the BOP; testing the BOP on the second pipe when the testtool is in a first operational configuration; testing the BOP on thefirst pipe when the test tool is in a second operational configuration;testing the BOP in an empty space through which a longitudinal axis ofthe first sub extends when the test tool in a third operationalconfiguration, the empty space being located between the first pipe andthe first sub; and removing the test tool and the plug from the BOP andthe wellhead, wherein the test tool is not removed from the BOP and thewellhead until after the plug is sealingly engaged with the wellhead,the BOP is tested on the second pipe, the BOP is tested on the firstpipe, and the BOP is tested in the empty space. In an exemplaryembodiment, when the test tool is in the first operationalconfiguration: the first pipe is connected to the first sub andpositioned in a first axial position relative to the first sub; thesecond pipe is connected to the second sub; and the second sub isconnected to the first sub and positioned in a first axial positionrelative to the first pipe so that the first pipe extends within thefirst sub, the second sub, and the second pipe. In an exemplaryembodiment, when the first pipe is connected to the first sub: first andsecond generally frusto-conical surfaces of the first sub are engaged,or nearly engaged, by first and second generally frusto-conical surfacesof the first pipe; and one or more sealing elements extending within oneor more annular grooves in the first surface of the first pipe sealinglyengage the first surface of the first sub. In an exemplary embodiment,when the second sub is connected to the first sub: third and fourthgenerally frusto-conical surfaces of the first sub are engaged, ornearly engaged, by first and second generally frusto-conical surfaces ofthe second sub; and one or more sealing elements extending within one ormore annular grooves in the first and second surfaces of the second subsealingly engage the third and fourth surfaces, respectively, of thefirst sub. In an exemplary embodiment, after testing the BOP on thesecond pipe, the method further includes: actuating the test tool fromthe first operational configuration to the second operationalconfiguration; and, when the test tool is in the second operationalconfiguration: the first pipe is connected to the first sub andpositioned in the first axial position relative to the first sub; thesecond pipe is connected to the second sub; and the second sub isdisconnected from the first sub and positioned in a second axialposition relative to the first pipe so that the first pipe extendswithin the first sub and the second sub. In an exemplary embodiment,actuating the test tool from the first operational configuration to thesecond operational configuration includes: rotating the second subrelative to the first sub to threadably disengage an external threadedconnection of the second sub from a first internal threaded connectionof the first sub; and axially displacing the second sub relative to thefirst pipe from the first axial position to the second axial position.In an exemplary embodiment, when the second sub is positioned in thesecond axial position relative to the first pipe, a torque istransferable from the second sub to the first pipe. In an exemplaryembodiment, after testing the BOP on the first pipe, the method furtherincludes actuating the test tool from the second operationalconfiguration to the third operational configuration; and wherein, whenthe test tool is in the third operational configuration: the first pipeis disconnected from the first sub and positioned in a second axialposition relative to the first sub; the second pipe is connected to thesecond sub; and the second sub is disconnected from the first sub andpositioned in the second axial position relative to the first pipe sothat the first pipe extends within the second sub. In an exemplaryembodiment, actuating the test tool from the second operationalconfiguration to the third operational configuration includes: rotatingthe first pipe relative to the first sub to threadably disengage anexternal threaded connection of the first pipe from a second internalthreaded connection of the first sub; and axially displacing the firstpipe relative to the first sub from the first axial position to thesecond axial position. In an exemplary embodiment, rotating the firstpipe relative to the first sub includes transferring a torque from thesecond sub to the first pipe via a complementary engagement between aninternal spline of the second sub and an external spline of the firstpipe.

In several exemplary embodiments, while different steps, processes, andprocedures are described as appearing as distinct acts, one or more ofthe steps, one or more of the processes, and/or one or more of theprocedures may also be performed in different orders, simultaneouslyand/or sequentially. In several exemplary embodiments, the steps,processes and/or procedures may be merged into one or more steps,processes and/or procedures.

In several exemplary embodiments, one or more of the operational stepsin each embodiment may be omitted. Moreover, in some instances, somefeatures of the present disclosure may be employed without acorresponding use of the other features. Moreover, one or more of theabove-described embodiments and/or variations may be combined in wholeor in part with any one or more of the other above-described embodimentsand/or variations.

In the foregoing description of certain embodiments, specificterminology has been resorted to for the sake of clarity. However, thedisclosure is not intended to be limited to the specific terms soselected, and it is to be understood that each specific term includesother technical equivalents which operate in a similar manner toaccomplish a similar technical purpose. Terms such as “left” and right”,“front” and “rear”, “above” and “below” and the like are used as wordsof convenience to provide reference points and are not to be construedas limiting terms.

In this specification, the word “comprising” is to be understood in its“open” sense, that is, in the sense of “including”, and thus not limitedto its “closed” sense, that is the sense of “consisting only of”. Acorresponding meaning is to be attributed to the corresponding words“comprise”, “comprised” and “comprises” where they appear.

In addition, the foregoing describes only some embodiments of theinvention(s), and alterations, modifications, additions and/or changescan be made thereto without departing from the scope and spirit of thedisclosed embodiments, the embodiments being illustrative and notrestrictive.

Furthermore, invention(s) have described in connection with what arepresently considered to be the most practical and preferred embodiments,it is to be understood that the invention is not to be limited to thedisclosed embodiments, but on the contrary, is intended to cover variousmodifications and equivalent arrangements included within the spirit andscope of the invention(s). Also, the various embodiments described abovemay be implemented in conjunction with other embodiments, e.g., aspectsof one embodiment may be combined with aspects of another embodiment torealize yet other embodiments. Further, each independent feature orcomponent of any given assembly may constitute an additional embodiment.

What is claimed is:
 1. A test tool for a blowout preventer, the testtool comprising: a first sub; a first pipe disconnectably connected tothe first sub and positioned in a first axial position relative to thefirst sub, the first pipe comprising an external spline; a second subdisconnectably connected to the first sub and positioned in a firstaxial position relative to the first pipe so that the first pipe extendswithin the first sub, the second sub, and a second pipe, the second subcomprising an internal spline engageable with the external spline of thefirst pipe so that a torque is transferable from the second sub to thefirst pipe; and the second pipe being connected to the second sub. 2.The test tool of claim 1, wherein the first pipe is disconnectablyconnected to the first sub via a threaded engagement between an externalthreaded connection of the first pipe and a first internal threadedconnection of the first sub; and wherein the second sub isdisconnectably connected to the first sub via a threaded engagementbetween an external threaded connection of the second sub and a secondinternal threaded connection of the first sub.
 3. The test tool of claim2, wherein the threaded engagement between the external threadedconnection of the first pipe and the first internal threaded connectionof the first sub causes: first and second generally frusto-conicalsurfaces of the first sub to be engaged, or nearly engaged, by first andsecond generally frusto-conical surfaces of the first pipe; and one ormore sealing elements extending within one or more annular grooves inthe first surface of the first pipe to sealingly engage the firstsurface of the first sub.
 4. The test tool of claim 3, wherein thethreaded engagement between the external threaded connection of thesecond sub and the second internal threaded connection of the first subcauses: third and fourth generally frusto-conical surfaces of the firstsub to be engaged, or nearly engaged, by first and second generallyfrusto-conical surfaces of the second sub; and one or more sealingelements extending within one or more annular grooves in the first andsecond surfaces of the second sub to sealingly engage the third andfourth surfaces of the first sub.
 5. The test tool of claim 1, whereinthe test tool is actuable so that: the first pipe is disconnectablyconnected to the first sub and positioned in the first axial positionrelative to the first sub; and the second sub is disconnected from thefirst sub and positioned in a second axial position relative to thefirst pipe so that the first pipe extends within the first sub and thesecond sub.
 6. The test tool of claim 5, wherein the positioning of thesecond sub in the second axial position relative to the first pipeengages the internal spline of the second sub with the external splineof the first pipe so that the torque is transferable from the second subto the first pipe via at least the engagement between the internalspline and the external spline.
 7. The test tool of claim 5, wherein thetest tool is further actuable so that: the first pipe is disconnectedfrom the first sub and positioned in a second axial position relative tothe first sub; and the second sub is disconnected from the first sub andpositioned in the second axial position relative to the first pipe sothat the first pipe extends within the second sub.
 8. The test tool ofclaim 7, wherein the positioning of the first pipe in the second axialposition relative to first sub spaces apart the first pipe from thefirst sub.
 9. The test tool of claim 1, wherein the first pipe isdisconnectably connected to the first sub via a threaded engagementbetween the first pipe and the first sub; and wherein the threadedengagement between the first pipe and the first sub causes a generallyfrusto-conical surface of the first sub to be engaged, or nearlyengaged, by a generally frusto-conical surface of the first pipe. 10.The test tool of claim 9, wherein the threaded engagement between thefirst pipe and the first sub further causes a sealing element extendingwithin an annular groove in the generally frusto-conical surface of thefirst pipe to sealingly engage the generally frusto-conical surface ofthe first sub.
 11. The test tool of claim 1, wherein the second sub isdisconnectably connected to the first sub via a threaded engagementbetween the second sub and the first sub; and wherein the threadedengagement between the second sub and the first sub causes a generallyfrusto-conical surface of the first sub to be engaged, or nearlyengaged, by a generally frusto-conical surface of the second sub. 12.The test tool of claim 11, wherein the threaded engagement between thesecond sub and the first sub further causes a sealing element extendingwithin an annular groove in the generally frusto-conical surface of thesecond sub to sealingly engage the generally frusto-conical surface ofthe first sub.